JP5552022B2 - Lighting device and lighting apparatus using the same - Google Patents

Description

  The present invention relates to a lighting device and a lighting fixture using the same.

  Conventionally, a lighting device using a light emitting diode (LED) as a light source has been provided. In the conventional lighting device, in order to perform dimming control of the LED, PWM dimming that intermittently pauses the LED current flowing through the LED at a low frequency of about 100 Hz to several kHz, and amplitude dimming that controls the amplitude of the LED current. It is carried out. PWM dimming performs dimming control of the LED by adjusting the period (on duty) for supplying the LED current to the LED using the PWM signal and adjusting the average value of the light output (LED current). Amplitude dimming performs dimming control of the LED by adjusting the magnitude (amplitude) of the LED current and adjusting the average value of the light output (LED current).

  There is also provided an LED dimming device that performs amplitude dimming in a region where the dimming level is high and performs PWM dimming in a region where the dimming level is low (see Patent Document 1).

  When performing PWM dimming in synchronization with the PWM signal, it is desirable to set the frequency of the PWM signal (PWM frequency) to 100 Hz or more in order to suppress LED flicker. By setting the PWM frequency to 100 Hz or higher, the human eye does not feel flicker under the environment where the LED irradiates. However, when the PWM frequency is set to 2 kHz or more, the on / off time is shortened in a region where the dimming level is deep, so the number of on pulses of the switching element cannot be finely controlled, and the number of on pulses changes discretely. The dimming resolution is reduced. Furthermore, a beat is generated by a transformer or the like. Therefore, when performing PWM dimming, it is desirable to set the PWM frequency to 100 Hz to 2 kHz.

JP 2009-123681 A

  A device for displaying 3D video (stereoscopic video) such as a 3D television is provided within the illumination range by using a lighting device that performs PWM dimming for indoor lighting or outdoor nighttime lighting. In this case, there is a problem that flickering occurs in the user's field of view when the user wears 3D glasses for stereoscopically viewing the video.

  The basic principle of displaying a 3D image is to create a parallax artificially by separately capturing images for the left eye and the right eye, and to recognize the image, depth, and stereoscopic effect in the viewer's brain.

  For example, in the case of 3D television, a frame sequential method is used in which a left-eye image projected on the left eye and a right-eye image projected on the right eye are alternately displayed frame by frame. Specifically, the 3D glasses include a pair of lenses for the right eye and the left eye, and a shutter that blocks a light transmitting surface of each lens. When the left-eye video is displayed, the right-eye field of view is blocked by the shutter of the 3D glasses so that only the left eye can see. Conversely, when the right-eye video is displayed, the left-eye field of view is blocked by the shutter of the 3D glasses in order to view only with the right eye. In this way, by synchronizing the timing for switching the frame of 3D video and the timing for opening and closing the left and right shutters of the 3D glasses using infrared signals or the like, the depth and stereoscopic effect of the video can be recognized.

  Usually, the number of frames displayed on a 3D television per second is 60 frames on the left and right (60 Hz), for a total of 120 frames. In addition, the shutter speed (shutter frequency) for alternately opening and closing the left and right shutters of the 3D glasses varies depending on the model and region, such as 25 Hz, 30 Hz, and 60 Hz.

  For example, when the light source is PWM dimmed using a PWM signal with a PWM frequency of 100 Hz, the light source repeats blinking at 100 Hz. Under such an environment, for example, if the shutter of the 3D glasses repeatedly opens and closes at a shutter speed of 60 Hz (total of 120 times left and right per second = 120 Hz), the PWM frequency and the shutter speed cannot be synchronized. That is, when the light source blinks and the shutter opens and closes and the 3D glasses are worn, flickering occurs in human eyes.

  Further, according to the experimental results, when PWM dimming is performed, even if the frequency component of the PWM frequency included in the output light (output current) is several percent or less, that is, the dimming state is close to full lighting, flickering occurs. I was able to feel it.

  Furthermore, since the shutter frequency varies depending on the model or region, the PWM frequency at which flickering occurs differs, and it is necessary to individually set the PWM frequency for each model or region.

  The present invention has been made in view of the above-described reasons, and an object of the present invention is to support a plurality of 3D glasses having different shutter frequencies and to prevent occurrence of flicker when the 3D glasses are worn. And it is providing the lighting fixture using this.

  The lighting device according to the present invention is used in a space using 3D glasses including a shutter that alternately cuts off each light-transmitting surface of a pair of lenses at any one of the plurality of shutter frequencies. A lighting unit that outputs a direct current to the light source, and a dimming unit that turns on and off the supply of the direct current to the light source at a predetermined PWM frequency, wherein the PWM frequency is a minimum of the plurality of types of shutter frequencies. It is an integral multiple of the common multiple.

  In this lighting device, the PWM frequency is preferably an even multiple of the least common multiple.

  The lighting device preferably includes a timing synchronization unit that matches a timing at which the supply of the direct current to the light source is turned on or off with a timing at which the shutter of the lens of the 3D glasses is opened or closed.

  The luminaire of the present invention is used in a space using 3D glasses in which shutters that cut off the light-transmitting surfaces of a pair of lenses at any one of the plurality of shutter frequencies are alternately opened and closed. A lighting unit that outputs a direct current to the light source, and a dimming unit that turns on and off the supply of the direct current to the light source at a predetermined PWM frequency, wherein the PWM frequency is a minimum of the plurality of types of shutter frequencies. A lighting device that is an integral multiple of a common multiple, and a light source that is lit by the direct current output from the lighting device.

  As described above, the present invention is compatible with a plurality of 3D glasses having different shutter frequencies, and has an effect of preventing occurrence of flicker when the 3D glasses are worn.

It is a circuit block diagram of the lighting device of Embodiment 1 of this invention. It is a block diagram which shows the internal structure of the integrated circuit for control same as the above. (A) It is a wave form diagram of LED current. (B) It is a wave form diagram of a PWM signal. (A) It is a wave form diagram of LED current. (B) It is a wave form diagram of a PWM signal. It is a schematic block diagram which shows the external appearance of 3D glasses. It is a schematic block diagram which shows the external appearance of the lighting fixture of Embodiment 2. FIG.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(Embodiment 1)
The circuit block diagram of the lighting device 1 of this embodiment is shown in FIG.

  The lighting device 1 of this embodiment includes a power supply circuit 2, a step-down chopper circuit 3, a control circuit 4, and a control power supply circuit 5. The step-down chopper circuit 3 corresponds to the lighting unit of the present invention, and the control circuit 4 corresponds to the dimming unit of the present invention.

  The lighting device 1 is supplied with power from a commercial power supply 100 (for example, 100 V, 50/60 Hz) via a connector CON1, and the power supply circuit 2 converts the alternating voltage V1 to generate a rectified voltage V2. The step-down chopper circuit 3 is connected to the light source 6 via the connector CON2. The light source 6 of this embodiment is composed of one or more semiconductor light emitting elements 61 (LED elements 61). The light source 6 may be constituted by an LED module in which a plurality of LED elements 61 are connected in series, parallel, or series-parallel. In this embodiment, the LED element 61 is used as the semiconductor light emitting element, but an organic EL element or a semiconductor laser element may be used.

  The control circuit 4 can perform dimming control of the light source 6 by controlling the output current of the step-down chopper circuit 3 based on the PWM signal S1.

  The detailed configuration of each part will be described below.

  The power supply circuit 2 includes a fuse F1, a filter circuit 21, and a rectifying / smoothing circuit 22.

  The filter circuit 21 is supplied with the AC voltage V1 from the commercial power supply 100 via the connector CON1 and the fuse F1. The filter circuit 21 includes a surge voltage absorbing element ZNR1, capacitors C1 and C2, and a common mode choke coil LF1, and removes noise from the AC voltage V1 supplied from a commercial power source.

  The rectifying / smoothing circuit 22 includes a full-wave rectifier DB1 and a smoothing capacitor C3, and rectifies and smoothes the AC voltage V1 to generate a rectified voltage V2 between both ends of the smoothing capacitor C3. Note that the rectifying / smoothing circuit 22 may be configured by a power factor correction circuit using a boost chopper circuit.

  Since the power supply circuit 2 has a conventionally well-known circuit configuration, detailed description thereof is omitted.

  Next, the step-down chopper circuit 3 will be described.

  The step-down chopper circuit 3 includes an inductor L1, a switching element Q1 composed of an n-channel MOSFET, a diode D1, and a capacitor C4 composed of an electrolytic capacitor. A series circuit including a capacitor C4, an inductor L1, a switching element Q1, and a resistor R1 is connected between the output terminals of the rectifying / smoothing circuit 22, and a diode D1 is connected in parallel with the capacitor C4 and the inductor L1.

  A light source 6 is connected between both ends of the capacitor C4 via a connector CON2.

  When the switching element Q1 is on, a DC current I1 for charging the capacitor C4 flows from the rectifying and smoothing circuit 22, and the capacitor C4 is charged. When the switching element Q1 is off, the direct current I1 stops flowing and the capacitor C4 is discharged. As described above, the switching element Q1 is alternately turned on and off alternately, and the capacitor C4 is repeatedly charged and discharged, whereby the rectified voltage V2 is stepped down to generate the capacitor voltage V3 across the capacitor C4. Then, the LED current I2 is supplied to the light source 6 using the capacitor voltage V3 as a power source.

  The control circuit 4 controls the LED current I2 and controls the light source 6 by controlling the switching of the switching element Q1. The control circuit 4 includes a control integrated circuit 41 and its peripheral circuits.

  FIG. 2 shows an internal configuration of the control integrated circuit 41.

  The INV pin 411 is connected to the inverting input terminal of the built-in error amplifier EA1 (error amplifier). The COMP pin 412 is connected to the output terminal of the error amplifier EA1. The MULT pin 413 is connected to the input terminal of the multiplication circuit 43. The CS pin 414 functions as a chopper current detection terminal. The ZCD pin 415 functions as a zero cross detection terminal. The GND pin 416 functions as a ground terminal. The GD pin 417 functions as a gate drive terminal. The Vcc pin 418 functions as a power supply terminal.

  When a control power supply voltage V4 equal to or higher than a predetermined voltage is applied between the Vcc pin 418 and the GND pin 416, reference voltages V5 and V6 are generated by the built-in control power supply 42. Then, each circuit inside the control integrated circuit 41 can operate.

  Further, in the present embodiment, the control power supply circuit 5 in which the capacitor C5 and the Zener diode ZD1 are connected in parallel to each other is provided, and the control power supply voltage V4 set to the Zener voltage of the Zener diode ZD1 is generated. As a simple configuration, a high resistance (not shown) is connected between the positive electrode of the capacitor C3 and the positive electrode of the capacitor C5, and the rectified voltage V2 output from the rectifying and smoothing circuit 22 is used as the input of the control power supply circuit 5.

  When the control power supply voltage V4 is applied to the control integrated circuit 41, the starter 44 first outputs a start pulse to the set input terminal 451 (S terminal) of the flip-flop 45 via the OR gate 46. Then, the output level of the output terminal 452 (Q terminal) of the flip-flop 45 becomes a high level. Then, the output level of the GD pin 417 also becomes a high level via the drive circuit 47.

  A series circuit of resistors R2 and R3 is connected between the GD pin 417 and the ground, and a connection point between the resistors R2 and R3 is connected to the gate of the switching element Q1. Therefore, when the output level of the GD pin 417 becomes a high level, the resistance divided value by the resistors R2 and R3 is applied between the gate and the source of the switching element Q1, and the switching element Q1 is turned on. The resistor R1 is a resistor having a small resistance value used for current detection, and therefore hardly affects the voltage applied between the gate and the source.

  When the switching element Q1 is turned on, a direct current I1 flows from the rectifying / smoothing circuit 22 through the path of the capacitor C4, the inductor L1, the switching element Q1, and the resistor R1. At this time, the direct current I1 flowing through the inductor L1 rises substantially linearly unless the inductor L1 is magnetically saturated. The resistor R1 is a detection resistor for the DC current I1 when the switching element Q1 is on, and the voltage V7 across the resistor R1 serves as a detection signal for the DC current I1, and the CS pin 414 of the control integrated circuit 41. Is output.

  The voltage V7 input to the CS pin 414 is applied to the non-inverting input terminal of the comparator CP1 through a noise filter composed of a resistor R4 and a capacitor C8. In the present embodiment, the resistor R4 is 40 kΩ, and the capacitor C8 is 5 pF. A reference voltage V8 is applied to the inverting input terminal of the comparator CP1. The reference voltage V8 is an output voltage of the multiplication circuit 43, and is determined based on the voltage V9 applied to the INV pin 411 and the voltage V10 applied to the MULT pin 413.

  When the DC current I1 flowing through the inductor L1 exceeds a predetermined value and the voltage V7 across the resistor R1 exceeds the reference voltage V8, the output level of the comparator CP1 becomes high level, and the reset input terminal 453 (R terminal) of the flip-flop 45 is connected. A high level signal is input. Then, the output level of the output terminal 452 (Q terminal) of the flip-flop 45 becomes a low level. When the output level of the output terminal 452 (Q terminal) becomes a low level, the output level of the drive circuit 47 also becomes a low level and operates so as to draw a current from the GD pin 417. A series circuit of a diode D2 and a resistor R5 is connected in parallel with the resistor R2, and the drive circuit 47 extracts the charge between the gate and the source of the switching element Q1 via the diode D2 and the resistor R5, thereby switching the switching element Q1. Will turn off promptly.

  When the switching element Q1 is turned off, the electromagnetic energy accumulated in the inductor L1 flows through the diode D1 and a regenerative current flows, and the capacitor C4 is discharged. At this time, the voltage across the inductor L1 is clamped to the voltage V3 across the capacitor C4. When the inductance of the inductor L1 is L1a, the regenerative current flowing through the inductor L1 decreases with a substantially constant slope (di / dt≈−V3 / L1a).

  When the capacitor voltage V3 generated across the capacitor C4 is high, the regenerative current decays rapidly, and when the capacitor voltage V3 is low, the regenerative current decays slowly. That is, even if the peak value of the regenerative current flowing through the inductor L1 is constant, the time until the regenerative current disappears changes according to the load voltage. The required time is shorter as the capacitor voltage V3 is higher and longer as the capacitor voltage V3 is lower.

  Further, during the period when the regenerative current is flowing, a secondary voltage V11 corresponding to the gradient of the regenerative current is generated between both ends of the secondary winding L11 of the inductor L1, and this secondary voltage V11 is detected by the regenerative current. A signal is output to the ZCD pin 415 via the resistor R6. The secondary voltage V11 becomes zero when the regenerative current finishes flowing.

  The ZCD pin 415 is connected to the inverting input terminal of the comparator CP2 for detecting zero crossing. The reference voltage V6 is applied to the non-inverting input terminal of the comparator CP2. When the regenerative current decreases and the secondary voltage V11 becomes equal to or lower than the reference voltage V6, the output level of the comparator CP2 becomes a high level and goes high via the OR gate 46 to the set input terminal 451 (S terminal) of the flip-flop 45. A level signal is output. Then, the output level of the output terminal 452 (Q terminal) of the flip-flop 45 becomes high level, the output level of the GD pin 417 becomes high level, and the switching element Q1 is turned on.

  Thus, by repeating the above operation, the switching element Q1 is turned on / off, the capacitor voltage V3 obtained by stepping down the rectified voltage V2 is generated between both ends of the capacitor C4, and the LED current I2 supplied to the light source 6 is determined. Current controlled. The light source 6 is configured by connecting a plurality of LED elements 61 in series. When the forward voltage of the LED elements 61 is Vf and the number of the LED elements 61 connected in series is n, the capacitor voltage V3. Is clamped to approximately Vf × n.

  Next, dimming control of the light source 6 will be described.

  The lighting device according to the present embodiment performs intermittent control for intermittently stopping the high-frequency chopper operation in accordance with a low-frequency PWM signal S1 transmitted from, for example, a dimmer (not shown). The LED current I2 corresponding to the duty is supplied to the light source 6 for dimming.

  A switching element Q2 composed of an n-channel MOSFET is connected between the gate terminal of the switching element Q1 and the ground, and the PWM signal S1 is output to the gate terminal of the switching element Q2.

  The PWM signal S1 is a low-frequency rectangular wave voltage signal with a PWM frequency of, for example, about 100 Hz to 2 kHz, and is configured such that the light control level increases as the low level period in one cycle increases. This type of PWM signal S1 is widely used in dimming lighting devices such as fluorescent lamps.

  When the PWM signal S1 is at a high level, the switching element Q2 is turned on, so that the gate terminal of the switching element Q1 and the ground are short-circuited. That is, when the PWM signal S1 is at the high level, the OFF state of the switching element Q1 is maintained regardless of the output level of the GD pin 417, and the chopper operation (switching operation of the switching element Q1) is stopped. Since the DC current I1 is not supplied from the rectifying / smoothing circuit 22 to the capacitor C4 during the chopper operation stop period, the capacitor C4 is discharged and the capacitor voltage V3 decreases.

  When the PWM signal S1 is at a low level, the switching element Q2 is turned off (high impedance state). That is, when the PWM signal S1 is at a low level, a normal chopper operation in which the switching element Q1 is turned on / off is performed according to the output level of the GD pin 417. During the chopper operation period, since the switching element Q1 is turned on / off, the capacitor voltage V3 is generated across the capacitor C4, and the LED current I2 is supplied to the light source 6.

  Therefore, the ratio between the chopper operation period and the chopper operation stop period coincides with the ratio (duty ratio) between the low level period and the high level period of the PWM signal S1. Since the capacitor voltage V3 increases in the chopper operation period T1, the LED current I2 increases. In the chopper operation stop period T2, the capacitor voltage V3 decreases, and thus the LED current I2 decreases. That is, the LED current I2 corresponding to the ratio of the low level with respect to one period T0 of the PWM signal S1 is supplied to the light source 6. That is, the light source 6 can be dimmed (PWM dimming) by changing the duty ratio of the PWM signal S2.

  When the PWM frequency is constant, the ripple of the LED current I2 supplied to the light source 6 is determined by the capacitance of the capacitor C4. As shown in FIG. 3, when the capacitance of the capacitor C4 is small, the LED current I2 in the period T1 during which the chopping operation is stopped rapidly decays. However, as shown in FIG. 4, when the capacitance of the capacitor C4 is large, the LED current I2 is slowly attenuated even during the period T1 during which the chopping operation is stopped, so that the ripple of the LED current I2 becomes small.

  Next, a schematic configuration diagram of the 3D glasses 7 is shown in FIG.

  The 3D glasses 7 are used for a device that displays 3D video (stereoscopic video) such as a 3D television, and can be stereoscopically viewed when worn by the user. The 3D glasses 7 of the present embodiment are compatible with frame sequential 3D video, and include a pair of lenses 71 for the right eye and for the left eye, and each lens 71 blocks the light-transmitting surface and blocks the field of view. Has a shutter. When the left-eye video is displayed from the 3D television, the shutter of the right-eye lens 71 is closed to block the right-eye view. Conversely, when the right-eye video is displayed from the 3D television, the shutter of the left-eye lens 71 is closed to block the left-eye view. As described above, the timing of switching the frame of the 3D video and the timing of alternately opening and closing the left and right shutters of the 3D glasses 7 are made to recognize the depth and stereoscopic effect of the video by using an infrared signal or the like. Can do.

  The shutter speed (shutter frequency) at which the shutter of the lens 71 of the 3D glasses 7 opens and closes varies depending on the model and region. For example, the shutter speed is 25 Hz in Europe, 30 Hz in the United States, and 60 Hz in Japan.

  When the lighting device 1 of the present embodiment is used in a space where the 3D glasses 7 are used, the lighting device of the present embodiment uses the lowest common multiple of the above three types of shutter speeds (25 Hz, 30 Hz, 60 Hz) as the PWM frequency. It is assumed that 300 Hz. Thereby, since the integer multiple of each shutter speed and the PWM frequency match, flickering can be prevented even when any of a plurality of 3D glasses 7 having different shutter speeds is attached.

  Further, the same effect as described above can be obtained even when the PWM frequency is set to an integral multiple (600 Hz, 900 Hz, 1200 Hz,...) Of the least common multiple (300 Hz) of the shutter speed. Note that when the PWM frequency is increased, a beat is generated in the inductor L1, and therefore the PWM frequency is preferably low.

  The lighting device of the present embodiment can correspond to a plurality of 3D glasses 8 having different shutter speeds, and it is not necessary to individually set the PWM frequency for each model or region, so that the cost can be reduced. Can be reduced.

  In addition, by setting the PWM frequency to an even multiple (600 Hz, 1200 Hz,...) Of the least common multiple (300 Hz) of the shutter speed, it is obtained from experimental results that the flicker when wearing 3D glasses is further reduced. It was. This is because the number of blinks of the light source 6 when the shutter is open is the same number on the left and right.

  The shutter speed is not limited to the above (25 Hz, 30 Hz, 60 Hz), and may be a different shutter speed. By setting the PWM frequency to an integer multiple of the least common multiple of a plurality of types of shutter speeds, Similar effects can be obtained.

  Moreover, as indicated by a broken line in FIG. 1, a timing synchronization unit 49 that matches the timing at which the chopper operation starts or stops and the timing at which the shutter of the 3D glasses 8 opens and closes may be provided. For example, the lighting device of the present embodiment is used as a lighting device for lighting the light source 6 attached to the 3D television, and an infrared signal transmitted from the 3D television and instructing the timing at which the shutter of the 3D glasses 7 is opened and closed is a timing synchronization unit. 49 receives. And the timing synchronization part 49 determines the timing which starts or stops a chopper operation | movement based on the received infrared signal. Thereby, the timing at which the chopper operation starts or stops can coincide with the timing at which the shutter of the 3D glasses 7 opens and closes, and flickering when the 3D glasses 7 are worn can be further reduced.

  Further, the control power supply circuit 5 of the present embodiment generates the control power supply V4 using the rectified voltage V2, but uses the secondary voltage V11 generated across the secondary winding L11 of the inductor L1, The control voltage V4 may be generated. By charging the capacitor C7 using the secondary voltage V11 during the chopper operation, the power efficiency can be improved.

  Further, in the present embodiment, the timing at which the regenerative current flowing through the inductor L1 becomes approximately 0 is detected by detecting the voltage V11 across the secondary winding L11 of the inductor L1, but the present invention is not limited to this method. For example, it is only necessary to detect the timing at which the regenerative current disappears, such as a method of detecting an increase in the reverse voltage of the diode D1 or a method of detecting a voltage drop between the drain and source of the switching element Q1.

  In the present embodiment, only PWM dimming for PWM control of the direct current I1 is performed. However, the same effect as described above can be obtained even when amplitude dimming for controlling the amplitude of the direct current I1 and PWM dimming are combined. Can be obtained. In this embodiment, by controlling the voltages V9 and V10 applied to the INV pin 411 or the MULT pin 413 of the control integrated circuit 41, the current flowing through the switching element Q1 can be controlled and the amplitude of the direct current I1 can be controlled. Amplitude dimming can be performed.

  In the internal configuration of the control integrated circuit 41 shown in FIG. 2, the DISABLE 48 has a function of stopping the drive circuit 47 when a predetermined voltage is applied to the ZCD pin 415.

(Embodiment 2)
The lighting fixture 8 of this embodiment is composed of the lighting device 1 of the first embodiment and the light source 6. In FIG. 6, the schematic sectional drawing of the lighting fixture 8 is shown.

  In the lighting fixture 8 of the present embodiment, the lighting device 1 that functions as a power supply unit and the light source 6 are configured separately and are electrically connected to each other using lead wires 11 and 65. By configuring the lighting device 1 and the light source 6 separately, the light source 6 can be thinned. Furthermore, the freedom degree of the installation place of the lighting device 1 improves.

  The light source 6 is an LED module that includes an LED element 61, an instrument housing 62, a light diffusion plate 63, and a mounting substrate 64, and is embedded so that one surface is exposed from the ceiling 9.

  The instrument housing 62 is formed of a metal cylinder having an opening on one side, and the opening is covered with a light diffusion plate 63. A mounting substrate 64 is installed on the bottom surface of the instrument housing 62 facing the light diffusing plate 63. A plurality of LED elements 61 are mounted on one surface of the mounting substrate 64, and the light emitted from the LED elements 61 is diffused by the light diffusion plate 63 and irradiated toward the floor surface.

  Since the lighting device 1 is configured separately from the light source 6, the lighting device 1 can be installed at a position away from the light source 6. In this embodiment, the lighting device 1 is installed on the back surface of the ceiling 9. Then, the output of the step-down chopper circuit 3 of the lighting device 1 is connected to the light source 6 via the lead wire 81 and the connector 82, and the LED current I 2 is supplied to the light source 6. The connector 82 is configured such that the connector 821 on the lighting device 1 side and the connector 822 on the light source 6 side are detachable, and the lighting device 1 and the light source 6 can be separated during maintenance.

  The lighting fixture 8 of the present embodiment includes the lighting device 1 described in the first embodiment, and thus corresponds to a plurality of 3D glasses 7 having different shutter speeds, and prevents flicker when the 3D glasses 7 are worn. be able to.

  In addition, in this embodiment, although the lighting device 1 and the light source 6 are comprised separately, you may comprise the lighting device 1 and the light source 6 integrally.

DESCRIPTION OF SYMBOLS 1 Lighting device 2 Power supply circuit 3 Step-down chopper circuit 4 Control circuit 5 Control power supply circuit 6 Light source 21 Filter circuit 22 Rectification smoothing circuit 41 Integrated circuit 61 for control LED element

Claims (4)

In a lighting device used in a space using 3D glasses having a shutter that alternately cuts off each light-transmitting surface of a pair of lenses at any one of the shutter frequencies among a plurality of types of shutter frequencies,
A lighting unit that outputs a direct current to the light source;
A dimmer that turns on and off the supply of the direct current to the light source at a predetermined PWM frequency;
The lighting device according to claim 1, wherein the PWM frequency is an integer multiple of a least common multiple of the plurality of types of shutter frequencies.   The lighting device according to claim 1, wherein the PWM frequency is an even multiple of the least common multiple.   3. The lighting device according to claim 1, further comprising a timing synchronization unit configured to match a timing at which the supply of the direct current to the light source is turned on or off with a timing at which a shutter of the lens of the 3D glasses is opened or closed. apparatus. An illumination fixture comprising: the lighting device according to any one of claims 1 to 3; and a light source that is turned on by the direct current output by the lighting device.

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